Trajectory Tracking Fault-tolerant Control for Distributed Drive Electric Vehicles Considering Steering Actuator Faults

Trajectory tracking control is a key component of vehicle autonomous driving technology. Compared with traditional vehicles, Distributed Driven Electric Vehicle (DDEV) is an ideal vehicle for trajectory tracking control because of its high space utilization, redundant control freedom and fast system response. However, the chassis execution system of DDEV has a relatively large number of sensors, which significantly increases its probability of failure. In this paper, we propose a trajectory tracking fault-tolerant control method for DDEV considering steering actuator faults. Firstly, we establish the dynamic model of the steering actuator and the trajectory tracking model of DDEV. The model is linearized and discretized by using Taylor series expansion and forward Euler method. Next, considering multi-objective constraints such as motion comfort, actuator saturation and road adhesion boundary, the trajectory tracking control strategy of DDEV is designed by using model predictive control theory and quadratic programming method. At the same time, we design the fitting formulas of tire longitudinal force, lateral force and aligning torque based on magic formula tire model. On this basis, a trajectory tracking fault-tolerant control strategy under steering actuator faults is designed using differential drive assisted steering principle and robust sliding mode control theory. Finally, we establish a joint simulation platform by MATLAB/Simulink and vehicle dynamics simulation software Carsim. The experimental results show that the designed trajectory tracking fault-tolerant control strategy could help DDEV to complete the trajectory tracking driving task well in the event of steering actuator failure.